“…Recently, the use of sulfonyl chlorides as sulfenylation reagents has been reported by You ( Scheme 2 , Equation (1)) [ 19 ], Zheng ( Scheme 2 , Equation (2)) [ 20 ] and our group ( Scheme 2 , Equations (3) and (4)) [ 21 ]. As a part of our on-going development of new sulfenylation methods [ 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 ], we report here a novel tetrabutylammonium iodide-facilitated thiolation of oxindoles with sulfonyl chlorides as sulfenylation reagents ( Scheme 3 ).…”